avoid circular init

pycbc/inference/__init__.py

@@ -2,3 +2,7 @@
 # pylint: disable=unused-import
 from . import (models, sampler, io)
 from . import (burn_in, entropy, gelman_rubin, geweke, option_utils)
+from .plugin import retrieve_model_plugins as _retrieve_model_plugins
+
+
+_retrieve_model_plugins(models.models, autoinit=True)

pycbc/inference/plugin.py

@@ -0,0 +1,67 @@
+# Copyright (C) 2022  Collin Capano
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by the
+# Free Software Foundation; either version 3 of the License, or (at your
+# option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
+# Public License for more details.
+#
+# You should have received a copy of the GNU General Public License along
+# with this program; if not, write to the Free Software Foundation, Inc.,
+# 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+
+#
+# =============================================================================
+#
+#                                   Preamble
+#
+# =============================================================================
+#
+
+"""Utilities for plugin model discovery."""
+
+_autoinit = False
+def retrieve_model_plugins(model_dict, autoinit=False):
+    """Retrieves and processes external model plugins.
+    """
+    # Avoid circular auto initialization
+    global _autoinit
+    if autoinit and _autoinit:
+        return
+    elif autoinit:
+        _autoinit = True
+
+    import pkg_resources
+    # Check for fd waveforms
+    for plugin in pkg_resources.iter_entry_points('pycbc.inference.models'):
+        add_custom_model(plugin.resolve(), model_dict)
+
+
+def add_custom_model(model, models, force=False):
+    """Makes a custom model available to PyCBC.
+
+    The provided model will be added to the dictionary of models that PyCBC
+    knows about, using the model's ``name`` attribute. If the ``name`` is the
+    same as a model that already exists in PyCBC, a :py:exc:`RuntimeError` will
+    be raised unless the ``force`` option is set to ``True``.
+
+    Parameters
+    ----------
+    model : pycbc.inference.models.base.BaseModel
+        The model to use. The model should be a sub-class of
+        :py:class:`BaseModel <pycbc.inference.models.base.BaseModel>` to ensure
+        it has the correct API for use within ``pycbc_inference``.
+    force : bool, optional
+        Add the model even if its ``name`` attribute is the same as a model
+        that is already in :py:data:`pycbc.inference.models.models`. Otherwise,
+        a :py:exc:`RuntimeError` will be raised. Default is ``False``.
+    """
+    #from pycbc.inference.models import models
+    if model.name in models and not force:
+        raise RuntimeError("Cannot load plugin model {}; the name is already "
+                           "in use.".format(model.name))
+    models[model.name] = model